Derivative financial instruments (Details 2) (USD $)	12 Months Ended
	Jan. 31, 2014	Feb. 01, 2013	Feb. 03, 2012
Pre-tax effect of derivative instruments on the condensed consolidated statements of comprehensive income
Loss related to effective portion of derivative recognized in OCI	$ 16,036,000	$ 9,626,000	$ 3,836,000
Loss related to effective portion of derivative reclassified from Accumulated OCI to Interest expense	4,604,000	13,327,000	28,633,000
(Gain) loss related to ineffective portion of derivative recognized in Other (income) expense		(2,392,000)	312,000
Credit-risk-related contingent features
Fair value of interest rate swaps in a net liability position	4,200,000
Collateral or assets required to settle interest rate swap obligations, estimated termination value	4,200,000
Derivatives not designated as hedges
Derivative instruments held
Number of derivative instruments which are non-designated hedges	0
Noncurrent Other liabilities
Derivatives designated as hedging instruments
Derivative financial instruments	$ 4,109,000	$ 4,822,000